This component is used to make powerful and runtime-configurable timeseries charts. It is configured by defining a set of pens and axes. Each pen represents a series of data. Pens can be many different styles, such as line, area, bar, and shape. This chart automatically creates controls for picking the time range and for hiding or displaying pens.
The are three kinds of pens in the Easy Chart:
Modes: Realtime vs Historical
The Easy Chart can operate in 3 different modes. These modes affect the range of data that is displayed, the controls the user is shown, and whether or not the chart polls for data.
The Easy Chart has many properties, like other components, that control its behavior. Things like its Mode, Polling Rate, etc are configured via the properties. All of the setup for adding pens, axes, subplots, etc is its Customizer. You can also drag and drop Historian-enabled SQLTags onto the chart directly in the Designer to add those tags as chart pens.
The easy chart supports any number of Y-axes. To add an axis, go to the Axes tab of the chart customizer. When adding an axis, you get a number of options such as the type (numeric or logarithmic), label, color, autorange vs fixed range, and auto-ticks vs fixed ticks. You can also modify the position of the axis, but note that by default the Chart's Auto Axis Positioning property is enabled, which means that the chart will balance the axes automatically between left and right depending on demand. As pens are turned on and off by the user, only the axes that are used by visible pens are shown.
After you add your axes, you edit any pens that you want to use your new axes. Simply choose the new axis in the axis dropdown of the pen editing window.
The Subplots feature lets you break up the chart's plot area into multiple distinct subplots that share the X axis, but have their own Y axes. This is often useful for digital data, as shown in the screenshot above. By default the chart has 1 subplot (the main plot). To add a new subplot, simply hit the add button in the Subplots tab of the chart customizer.
Subplots have relatively few options. The Weight option determines how much room the subplot gets relative to the other subplots. For example, in the screenshot above subplot #1's weight is 5, and subplot #2's weight is 1, leading to a 5-to-1 distribution of space. Just like axes, once you add your subplots you should go back to your pens and modify you pens' subplot property for any pens you want to appear on the subplot.
You can put your pens in groups to break up the pens into some logical separation. For instance, in the screenshot above there are three pen groups: C1, C2, and Valves. The group name is used as the titled border for the pens' grouping container. Groups also have another purpose, but it is more advanced and most people won't have to worry about it. For more, read the Dynamic Pens section below.
In is often the case that you'll want to make one chart window that services many similar pieces of equipment. For instance, if you have 30 tanks and they all have the same datapoints, you want to be able to use one window for all 30 of them and simply pass the tank number into the chart window as a parameter. There are actually a number of ways to accomplish this, each method suitable for different scenarios.
Database pens have 2 ways to be made dynamic. The first is the Chart's Where Clause property. This is a snippet of SQL where clause syntax, like "machine_num = 28" that will be included for all database pens in their queries. The second is to use a dynamic group. Any group can be made a dynamic group in the customizer. For each dynamic group, the easy chart will get a special dynamic property associated with that group. That property is another snippet of SQL where clause that will be applied to all database pens in that group.
The other way to make your pens (and anything else about the chart) dynamic at runtime is to use dynamic configuration. Read on...
The Easy Chart is not just meant to be easy to configure, but also very powerful. In particular, there is an emphasis on the ability to make any configuration change dynamically in a client - not just statically in the Designer. While a bit of scripting or clever property binding may be required, the technique is very powerful. This is achieved by storing all of the settings that you alter in the customizer in a set of expert-level dataset properties. So altering the datasets alters the chart configuration. You can inspect these various datasets, which hold the pens, axes, and subplot information, to see their format. They all look up information by column name (case-insensitive). So, if you have pen configuration stored in a database, you can bind an indirect SQL Query binding to alter the chart's pen set at runtime.
The following event sets are fired by this component. See Component Event Handlers to learn more.
The easy chart has the following extension functions. See each function's doc string for usage details.